This picture shows the canal with a set of double locks in the distance.
Double locks
These double locks are a common feature along this canal and were intended to facilitate the huge amount of traffic during the industrial revolution and were built by people such as James Brindley the famous canal engineer.
They were used to raise or lower the barges up or down as the canal climbed over the higher terrain and they can often be found as a series of locks very close together. The barge would be hauled into the empty lock as seen below, then flooded to raise the water level and with it the barge and cargo.
A modern day powered barge leaving the lock having been raised to the new level. Modern barges are used soley for recreation, whereas in the past a family with children would have to share the barge with the cargo and usually it was their only home.
During the industrial era the barges would be pulled by horses along a tow-path that ran on one side or the other of the canal. It was a tedious job to keep un-harnessing the horse at each lock, or if the tow-path changed sides along the canal, so they used some clever designs.
Some cross over bridges are of a reversed letter ‘C’ shape if viewed from above, this allowed a horse with tow rope still attached to walk up a slope on one side of the bridge, cross over the bridge, walk back down the slope on the opposite side and then continue walking under the bridge along the opposite side canal tow-path, without ever unhitching the rope, all very clever.
Most locks however allowed the horse to continue walking up a cobbled slope at the side so that it could continue pulling the heavy barge fully into the lock.
This often meant that the towing ropes would cut deep grooves into the corners of brickwork and cause damage. To prevent this happening, they would fixed bars of iron onto the brickwork to take the wear. In this picture you can see the cut marks caused by countless thousands of tow ropes wearing the iron away in over a hundred years of use.
Of course the water has to go somewhere when a lock is emptied and in a series of locks it will be used again lower down the flight, This picture shows the water being released from a lock being emptied.
To be continued if you wish
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